Muscle contraction headache
Muscle contraction headache or Tension headaches, which were recently renamed tension-type headaches by the International Headache Society, are the most common type of headaches. The pain can radiate from the neck, back, eyes, or other muscle groups in the body. Tension-type headaches account for nearly 90% of all headaches. Nearly everyone will have at least one tension headache in their lifetime. Approximately 3% of population suffers from chronic-tension type headache. Frequency and duration Tension-type headaches can be episodic or chronic. Episodic tension-type headaches are defined as tension headaches occurring less than 15 days a month, whereas chronic tension headaches occur 15 days or more a month for at least 6 months. Tension headaches can last from minutes to days or even months, though a typical tension headache lasts 4-6 hours. Pain Tension headache pain is often described as a constant pressure, as if the head were being squeezed in a vice. The pain is frequently bilateral which means it is present on both sides of the head at once. Tension headache pain is typically mild to moderate, but may be severe. In contrast to migraine, the pain does not increase during exercise. Cause and pathophysiology Various precipitating factors may cause TTH in susceptible individuals http://www.emedicine.com/neuro/topic231.htm. One half of patients with TTH identify stress or hunger as a precipitating factor . * Stress - Usually occurs in the afternoon after long stressful work hours * Sleep deprivation * Uncomfortable stressful position and/or bad posture * Irregular meal time (hunger) * Eyestrain * Caffeine withdrawal It has long been believed that they are caused by muscle tension around the head and neck. One of the theories says that the main cause for tension type headaches and migraine is teeth clenching which causes a chronic contraction of the temporalis muscle. Although muscle tension may be involved, scientists now believe there is not one single cause for this type of headache. Another theory is that the pain may be caused by a malfunctioning pain filter which is located in the brain stem. The view is that the brain misinterprets information, for example from the temporal muscle or other muscles, and interprets this signal as pain. One of the main molecules which is probably involved is serotonin. Evidence for this theory comes from the fact that chronic tension-type headaches may be successfully treated with certain antidepressants such as amitriptyline. However, the analgesic effect of amitriptyline in chronic tension-type headache is not solely due to serotonin reuptake inhibition, and likely other mechanisms are involved. Recent studies of nitric oxide (NO) mechanisms suggest that NO may play a key role in the pathophysiology of CTTH. Ashina M, Lassen LH, Bendtsen L, Jensen R, Olesen J. Effect of inhibition of nitric oxide synthase on chronic tension-type headache: a randomized crossover trial. Lancet. 1999 Jan 23;353:287-9. The sensitization of pain pathways may be caused by or associated with activation of nitric oxide synthase (NOS) and the generation of NO. Patients with chronic tension-type headache have increased muscle and skin pain sensitivity, demonstrated by low mechanical, thermal and electrical pain thresholds. Hyperexcitability of central nociceptive neurons (in trigeminal spinal nucleus, thalamus, and cerebral cortex) is believed to be involved in the pathophysiology of chronic tension-type headache.Ashina S, Bendtsen L, Ashina M. Pathophysiology of tension-type headache. Curr Pain Headache Rep, 2005 Dec; 9:415-22. Recent evidence for generalized increased pain sensitivity or hyperalgesia in CTTH strongly suggests that pain processing in the central nervous system is abnormal in this primary headache disorder. Moreover, a dysfunction in pain inhibitory systems may also play a role in the pathophysiology of chronic tension-type headache. Pielsticker A, Haag G, Zaudig M, Lautenbacher S. Impairment of pain inhibition in chronic tension-type headache. Pain. 2005 Nov;118:215-23. Treatment Episodic tension-type headaches generally respond well to over-the-counter analgesics, such as paracetamol, ibuprofen or aspirin. The effect of the analgesic is boosted if either caffeine (a cup of coffee) or a dose of the sedative antihistamine diphenhydramine (Benadryl, 25mg) is taken at the same time. However, these medications should be avoided in cases of chronic tension headache, due to the risk of medication overuse headaches. Chronic tension-type headaches are more difficult to treat. Suggested therapies include: Non-pharmacological therapy: *Swimming two to three times a week *Acupuncture *Biofeedback *Massage *Heat pillow *Relaxation techniques like: **Jacobson's Progressive Muscle Relaxation **Autogenic training *The NTI Tension Suppression System Pharmacological therapy: *Amitriptyline *Mirtazapine Tension headaches are exacerbated by states or activities that induce muscle tension, such as stress. Avoiding such states can lessen the frequency of tension headaches. Tension headaches can also be secondary to other conditions, such as an upper respiratory infection or other virus. Often the best treatment for a mild tension headache that does not impair a person's ability to function is simple endurance. Many tension headache sufferers receive relief from sleep. However, it is always best to see your physician for a full work-up of the headaches. Prognosis Tension headaches that do not occur as a symptom of another condition are painful and annoying, but not harmful. It is usually possible to receive relief from treatment. Tension headaches that occur as a symptom of another condition are usually relieved when the underlying condition is treated. Frequent use of pain medications in patients with tension-type headache may lead to the development of medication overuse headache. See also *Migraine *Cluster headache *Rebound headache References Category:Headaches External links *About Headaches / Migraine *American Council for Headache Education *ClusterHeadaches.com *Help for Headaches and Migraine *National Headache Foundation *OUCH, Organization for Understanding Cluster Headaches *Prevent Your Headaches *World Headache Alliance *Headache - Migraine Release Headache Relief Information